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Comment Re:not fucking close (Score 1) 147

I don't think Biosphere 2 is a good model for a space trip. We need simplified engineered ecosystems that are optimized for food and oxygen production and low weight. Something more like the plant farms running on the ISS at the moment. It makes no sense to replicate Earth ecosystems.

Comment Re:Can the enemy actually shoot down the F35? (Score 1) 732

There are lots of reports about radar technologies that can penetrate stealth, since years. All you need is a radar system that does not rely on its own sender. It can work with mobile tower signals, the new Eurofighter radar will work with TV station signals afaik. It also works with multiple planes flying in formation, detecting the radar reflection from the other plane's senders. The Serbian radar system just used a longer wavelength than usual, that was already enough to penetrate stealth of the F117. Upgrading older planes with stealth-penetrating radar is also much cheaper than building a fleet of stealth fighters.

Comment Re: Looking more and more likely all the time... (Score 1) 518

Sorry ,that is rubbish. The cars don't move anymore due to friction, they would still move if it was the collision of spaceships for example. And impulse is not just a mathematical construct, it is an important quantity in physics. The conservation of impulse is used to make mechanical calculations. It gives additional constraints to the conservation of energy, and there is no other conserved entity that gives these contraints.

Comment Re: Looking more and more likely all the time... (Score 1) 518

Ok. It violates the conservation of momentum in classical physics, since there are no virtual particles in this. And I think in quantum mechanics the impulse of virtual particles is going somewhere normally. If pairs of virtual antiparticles form the sum of their impulses is zero. Virtual photons can exchange an impulse between charged particles. They take up an impulse and give it to another particle, but I think impulse does not disappear or come out of nothing.

Comment Re: Looking more and more likely all the time... (Score 1) 518

There are hints that it is actually a thermal effect. The drive is heating up, and the impulse seems to be measured after the drive is shut down, while it is still hot.
I would suspect that it is the same effect as in Crookes radiometer. This should be easy to test though.

Comment Re:Windows without a SSD isn't worth it (Score 1) 517

If you don't want to buy SSDs you need to do proper defragmentation. Not with the Windows defrag, that does not do anything good.
The problem with Windows itself for example is that all the system files get spread out all over the hard disc due to the updates. The ne files are copied in the next free space of the hard disc, which is different with each update. What you want is that all Windows system files are in one place, best at the beginning of the drive for fast access. Normal defrags don't do anything to fix that. They only defrag files, but leave the files spread out all over the disc.
I am using O&O Defrag in Complete/Name mode. This places Windows at the beginning of the drive and sorts everything by folders. This way my computers with spinning discs are nearly as fast as the ones with SSD.

Comment Re:It's not limited to the US (Score 2) 220

I believe that too. Parasites and disease evolve so that they don't kill their host, since they would die too then. But they weaken their hosts. The combination of several ones can be deadly due to this.
Leprosy disappeared in Europe when some big Tuberculosis epidemics came. People with Leprosy got infected quickly and died. Does is make sense to blame their dead on just one of the two diseases?
You can take any of the factors which are weakening bees away to solve the problem. Best would be to reduce all of them, but neonics are the only factor that can be reduced easily.

Comment Re:4th Dimension? (Score 1) 236

To make it more confusing, could that 4th dimension be the time? Meaning that a galaxy feels gravity from itself in earlier times.
Because of relativity this long-term gravitational effect has to move linearly with the objects through space, so it would kind of wobble with the galaxies when they moving relative to each other. When the galaxies collide the past gravitational effect would keep moving linearly.
Objects of all sizes would have this effect. But since planets moves around stars and stars don't move straight for long either the gravity can not build up over a long time, as it can on the scale of galaxies.

Somebody ought to cross ball point pens with coat hangers so that the pens will multiply instead of disappear.